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We report the improved catalytic performance of SnO 2 -CuO hybrid nanocatalysts synthesized by rationally designing and controlling the local heterojunctions structure. The SnO 2 nanoparticles (NPs) decorated CuO nanorods (NRs) (SnO 2 -CuO) with a mace-like structure and with various CuO : SnO 2 ratios were prepared via depositing pre-synthesized SnO 2 NPs on CuO NRs in the presence of polyvinylpyrrolidone molecules. The CuO NRs were obtained by a facile hydrothermal reaction using Cu(NO 3 ) 2 •3H 2 O as the precursor. The samples were characterized by X-ray diffraction, transmission electron microscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, and temperature-programmed reduction analyses. The results indicated that in the SnO 2 -CuO hybrid nanostructures, the heterojunctions were well generated as the SnO 2 NPs were well dispersed on the CuO NRs. Their catalytic performances were then explored via the Rochow reaction, in which solid silicon (Si) reacts with gaseous methyl chloride (MeCl) to produce dimethyldichlorosilane (M2). Compared to discrete CuO and SnO 2 as well as their physical mixture, the SnO 2 -CuO hybrids exhibit significantly enhanced M2 selectivity and Si conversion because of the enhanced synergistic interaction between SnO 2 and CuO due to the generated heterojunctions.This work demonstrates that the performance of heterogeneous catalysts can be improved by carefully designing and controlling its structures even maintaining the composition unchanged.CuO microspheres 17 have been prepared in our group as model catalysts for the Rochow reaction, and found that their catalytic performance mainly depends on the chemical composition, 18 particles size, 19 and surface structure. 16 However, the above catalysts still suffer from low M2 selectivity and/or Si conversion, which seriously hinder their further application. Therefore, more efficient Cu-based catalysts should be developed.Recently, CuO-based hetero-structured hybrid materials have caused strong attention owing to their distinct properties and high diversity in structure and composition. For instance, Avgouropoulos et al. prepared a series of CuO-CeO 2 catalysts which exhibited much better catalytic performance for the selective oxidation of CO than CuO alone. 20 Li et al. observed that the CuO-ZnO-ZrO 2 catalysts synthesized by a surfactant-assisted coprecipitation method showed higher catalytic activity than that of sole CuO as a result of more intimate contact at the interface between Cu species and ZnO and/or ZrO 2 . 21 More recently, we have grown flower-like ZnO on urchin-like CuO microspheres using a simple solvothermal method, and the hierarchical structure displayed better catalytic properties in M2 synthesis in comparison with the single CuO phase, probably because of the enhanced synergistic effect between ZnO and CuO. 22 However, the composite particles were still in the micrometer scale with limited particle contact and weak synergistic effect.On the other hand, to date there are few reports on preparing Cu...